Vacuum cleaner fan shaft seal



y 9 R. E. DUNBAR 2,352,947

VACUUM CLEANER FAN SHAFT SEAL Filed Feb. 3, 1942 Fig.1.

Inventor" Ralph E. Dunbafl His Attorney.

Patented July 4, 1944 I 2,352,947 VACUUM CLEANER FAN SHAFT SEAL Ralph E. Dunbar, East Cleveland, Ohio,

to Electric Vacuum Cleaner Company,

assig'nor Inc.,

Cleveland, Ohio, a corporation of New York 1 Application February ,3, 1942, Serial No. 429,378

2 Claims.

The present invention relates to a sealing arrangement for the fan shaft of a vacuum cleaner or other device handling dirt-laden air.

The object of my invention is to provide an improved sealing arrangement for keeping dirt out of the fan shaft bearing, and for a consideration of what I believe to be novel and my invention, attention is directed to the following description and the claims appended thereto.

In the accompanying drawing, Fig. 1 is a sectional elevation of a vacuum cleaner having a sealing arrangement for the fan shaft embodying my invention; and Fig. 2 is a sectional view taken on line 2-2 of Fig.1.

Referring to the drawing, there is shown a vacuum cleaner having a fan casing l provided with a suction inlet 2 for connection with a suction hose and an outlet 3 for connection with a bag or other suitable filter. At the rear of the fan casing is a motor housing 4 having a wall 5 which serves as a partition between the fanand motor housings and as a support for a hearing housing 6 enclosing an anti-friction bearing 1 in which the motor shaft 8 is Journaled. A fan 8a having a hub 8b is fixed on the motor shaft. 0n the fan chamber side of the bearin housing is a grease seal which comprises a felt packing ring 9 compressed against the inner wall of the bearing housing and against the fan shaft by a spring washer l0 arranged between the felt packing ring and the raceway ll of the bearing. The felt packing ring 9 is quite effective in retaining grease or lubricant within the bearing housing, but there is a tendency for dirt to work past the packing ring and mix with the lubricating grease and cause bearing failures. To keep dirt out of the bearing housing 6 I have provided a conical sealing member I! of oil resistant rubber such as that sold under the trade name Perbunan. The sealing member l2 has an outwardly extending flange it which is clamped between the fan casing side of a hollow projection I4 on the wall 5 and a sealing ring it, fixed to the wall 5. The sealing ring I5 is provided with a threaded aperture l8 into which is threaded a tube l1 carrying a grease cup Ill. The threaded aperture It is in alignment with a slot IS in the projection I4 and accordingly provides a passage for a fluid sealing medium such as a grease into the space between the projection It andthe bearing housing 6. The sealing medium is kept out of the bearing housingby the packing ring 9. It is, however, free to flow into the space between the inner surface of the conical sealing member I! and the fan hub 8b.

The sealing medium cooperates with the sealing member l2 to provide a dirt seal. The inside diameter of the conical sealing member I! is slightly less than the outside diameter of the fan hub 8b on which it bears so that the inherent resilience of the sealing member l2 tends to maintain a tight sealing contact. Despite the tightness of the sealing contact between the sealforces the dirty sealing medium out past the sealing member i2 into the fan casing where it is picked up by the air. It is important that the conical sealing member [2 havevless retaining ability than the felt sealing ring 9, as otherwise the addition of fresh sealing medium through the grease cup [8 would tend to force. the dirty sealing medium into the bearing.

What I claim as new and desire to secure by Letters Patent of the United States, 152 g 1. In a vacuum cleaner, a fan chamber having an inlet and an outlet for dust-1aden.air, a fan shaft projecting into the fan chamber, a bearing housing for the shaft having a wall presented to the fan chamber and a lubricant retaining seal between the fan shaft and said wall behind which the bearing is located, a sealing chamber for retaining a fluid sealing medium on the fan chamber side of said seal, provisions for forcing chamber and the sealing medium is kept out of contact with the bearing.

2. In a vacuum cleaner having a fan shaft bearing in one wall of the fan chamber, a dirt seal for the bearing comprising a sealing chamber for holding a fluid sealing medium in contact with the fan shaft and out of contact with the bearing, provisions for supplying sealing medium to the chamber, and seals on the bearing and fan chamber sides of the sealing chamber the seal on the fan chamber side being looser than the seal on the bearing sideand being yieldable under the pressure built up during the supplying of sealing medium to the chamber whereby .upon supplying fresh sealing medium to the chamber, the excess sealing medium with any dirt which may have leaked pastthe seal will be forced into the fan chamber; 1

RALPHE. DUNBAR. 

